Tubular chemical reactors: the "lumping approximation" and bifurcation of oscillatory states

We study axial heat and mass transfer in a highly diffusive tubular chemical reactor in which a simple reaction is occurring. Singular perturbation techniques are used to derive approximate equations governing the situation. Attention is then focused on the bifurcation of oscillatory states from steady operating characteristics. By means of numerical calculations and phase plane illustrations we follow the bifurcated periodic solution branches along their complete lengths

Multiplier-continuation algorthms for constrained optimization

Several path following algorithms based on the combination of three smooth penalty functions, the quadratic penalty for equality constraints and the quadratic loss and log barrier for inequality constraints, their modern counterparts, augmented Lagrangian or multiplier methods, sequential quadratic programming, and predictor-corrector continuation are described. In the first phase of this methodology, one minimizes the unconstrained or linearly constrained penalty function or augmented Lagrangian. A homotopy path generated from the functions is then followed to optimality using efficient predictor-corrector continuation methods. The continuation steps are asymptotic to those taken by sequential quadratic programming which can be used in the final steps. Numerical test results show the method to be efficient, robust, and a competitive alternative to sequential quadratic programming

Three Algorithms for a Class of Multidimensional Assignment Problems

The assignment problem of matching the elements of two sets at some cost or to some benefit is well known and can be solved in polynomial time. However, many applications, particularly those in remote sensing and computer vision, require matching elements from more than two sets at some cost. Such problems are called multidimensional assignment problems and are known to be NP-hard. For time-critical applications and nontrivial multidimensional assignment problems, fast near-optimal algorithms are the only alternative. This paper compares three such algorithms: greedy, limited branch and bound, and Lagrangian relaxation

The Potential for Evolutionary Responses to Cell-Lineage Selection on Growth Form and Its Plasticity in a Red Seaweed

Despite much theoretical discussion on the evolutionary significance of intraclonal genetic variation, particularly for modular organisms whose lack of germ-soma segregation allows for variants arising in clonal growth to contribute to evolutionary change, the potential of this variation to fuel adaptation remains surprisingly untested. Given intraclonal variation, mitotic cell lineages, rather than sexual offspring, may frequently act as units of selection. Here, we applied artificial selection to such lineages in the branching red seaweed Asparagopsis armata, targeting aspects of clonal growth form and growth-form plasticity that enhance light acquisition on patchy subtidal reefs and predicting that a genetic basis to intraclonal variation may promote significant responses that cannot accompany phenotypic variation alone. Cell-lineage selection increased variation in branch proliferation among A. armata genets and successfully altered its plasticity to light. Correlated responses in the plasticity of branch elongation, moreover, showed that cell-lineage selection may be transmitted among the plasticities of growth-form traits in A. armata via pleiotropy. By demonstrating significant responses to cell-lineage selection on growth-form plasticity in this seaweed, our study lends support to the notion that intraclonal genetic variation may potentially help clonal organisms to evolve adaptively in the absence of sex and thereby prove surprisingly resilient to environmental change

Orange County, Texas : water wells

Map of Orange County, Texas, showing location of wells for which data were obtained. "Prepared in cooperation with the United States Department of the Interior, Geological Survey."UT Librarie

Montgomery County, Texas : records of wells, drillers' logs, water analyses, and map showing location of wells

Map of Montgomery County, Texas, showing locations of water wells. "Prepared in cooperation with the United States Department of the Interior, Geological Survey."UT Librarie

Galveston county, Texas. Records of wells, drillers' logs, water analyses, and map showing location of wells (1939)

Map of Galveston County, Texas, showing locations of water wells listed. At head of title : Texas State Board of Water Engineers. "Mimeographed by Works Progress Administration Project 10443." "Prepared in cooperation with the United States Department of the Interior, Geological Survey."UT Librarie

Harris County, Texas : records of wells, drillers' logs, water analyses, and map showing location of wells

"Prepared in cooperation with the United States Department of the Interior, Geological Survey."UT Librarie

A Supplementary Description of Cypridina mariae and Rediagnosis of the Genus Cylindroleberis (Ostracoda: Myodocopa: Cylindroleberididae)

The ostracod family Cylindroleberididae is based on the genus Cylindroleberis Brady, 1868, and has a complicated nomenclatural history. The type species of Cylindroleberis is Cypridina mariae Baird, 1850. Baird described only the carapace, which had been considered lost. Thus, there was no reference point for the concept C. mariae or the genus Cylindroleberis. Baird's material has now been found in the Natural History Museum, London, U.K., and is illustrated here. To clarify the taxonomic status of C. mariae and Cylindroleberis, specimens were obtained from near the type locality, and a supplementary description is presented. This includes description of appendages, particularly the first antenna and mandible, which contain important diagnostic characters. This supplementary description provides important information about C. mariae, allowing a revision of the genus Cylindroleberis, and establishing a framework for future biological research on this ostracod group

Ruminal digestion of protein and fiber in duodenally canmilated cows treated with vitaferm.

Ruminal digestion of protein and fiber in duodenally canmilated cows treated with vitaferm